I like the new 5-man dungeon, Magister's Terrace. But having run it repeatedly in normal and heroic with various groups, I noticed that our success was pretty much determined by the amount of crowd control we brought. If besides a tank and a healer you have 3 dps classes with crowd control, like mages, warlocks, hunters, and rogues, the dungeon is totally doable. If you bring lets say an enhancement shaman, a retribution paladin, and a fury warrior and thus have no crowd control except tanking, doing Magister's Terrace becomes nearly impossible.
That makes me wonder why not all classes get *some* form of crowd control, so they can perform a useful role beyond pure damage dealing in a group.